The present invention relates to transducer-protector devices for biomedical haemodialysis lines, comprising:                a first element including in a single piece of moulded plastic material a tubular fitting of the female Luer Lock type, designed to be connected with a tubing of a haemodialysis machine, and an annular radial flange,        a second element including in a single piece of moulded thermoplastic material a tubular fitting and an annular radial flange permanently joined in sealed fashion to said annular radial flange of the first element with said tubular fittings arranged coaxially, and        a filtering membrane made of permeable material defining a sterile anti-contamination barrier, peripherally secured between said annular radial flanges.        
Such transducer-protector devices must have meet two fundamental requirements: in the first place, they must assure, in use, a perfect and total hermetic seal between the first tubular fitting and the tubing of the haemodialysis machine on one side, and the second tubular fitting and the line connected to the patient on the other side. In the second place, they must be sterilisable by any traditional system, and in particular by means of steam treatment. For this reason, the plastic materials whereof the first and the second element of the device are formed must have such characteristics as to assure the necessary structural and dimensional stability even when heated to the steam sterilisation temperature. Otherwise, any deformations of one and/or of the other radial flange could cause an incomplete securing of the peripheral edge of the filtering membrane between the two flanges and, consequently, the ineffectiveness of the sterile barrier which said membrane should instead assure.